/Engine/Source/Editor/UnrealEd/Public/CinematicExporter.h
The function is saving the dialog state in a user ini file and reload it from there. It is not changing the CDO.
void FillExportOptions ( bool bBatchMode, bool bShowOptionDialog, const [FString](API\Runtime\Core\Containers\FString) & FullPath, bool & OutOperationCanceled, bool & bOutExportAll )